U4037B Low Voltage Speech Circuit with Tone Ringer Interface Description TELEFUNKEN microelectronic’s low voltage speech and ringer interface circuit, U4037B performs all necessary speech, line interface functions and the tone ringer required in an electronic telephone set. The circuit is line powered and contains all components necessary for amplification of signals and adaption to the line. The power supply of U4037B provides the MCU during the ringing and the speech mode. Features Speech Circuit Tone Ringer Interface D Adjustable dc characteristic D Symmetrical input of microphone amplifier D Receiving amplifier for dynamic or piezo-electric D Adjustable volume via 2 bit D/A converter D Adjustable threshold earpieces D MCU power supply D Automatic line loss compensation D MCU controlled earphone gain 8 dB D Anti-clipping in transmit direction Benefits Applications D Low number of external components Standard, telephones, fax machines TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96 1 (6) Preliminary Information U4037B Block Diagram / Applications Tip Ring MUTE MIC1 MIC2 Microphone amplifier 620 W MICO TIN Transmit amplifier – + VL Control function Sidetone amplifier Mute control DTMF ST RDC 22 mF Receiver attenuation RECIN VI Supply current regulator Receiving amplifier SWAMP AGC AGC current generator RECO1 RECO2 VB VDD Receive volume control Supply VOL1 VOL2 MELI Ringer volume control OUT Bandgap reference GND 9879 Comparator with hysteresis RFO to mC Figure 1. Block diagram 2 (6) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96 U4037B Pin Description Pin Symbol OUT MELI RECO1 RECO2 GND ST TIN MICO MIC 1, MIC 2 VDD RECIN VL Function Buzzer output Melody input Output of the receiver amplifier Suitable for dynamic or piezoelectronic transducers Ground The output of the sidetone cancellation signal, which requires a balanced impedance of 8 to 10 times the subscribers line impedance to be connected to Pin VL. Input to the line output driver amplifier, transmit a.g.c. applied to this stage Transmit pre-amplifier output Inputs of symmetrical microphone amplifier with high common mode rejection ratio Regulated output voltage of for biasing the MCU Receive amplifier input The receiving amplification is regulated by an a.g.c. Positive supply voltage input to the device The current through this pin is modulated by the transmit signal. TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96 Pin Symbol SWAMP VOI1 VOI2 RFO VI RAGC DTMF MUTE VB RDC Function An external resistor (1 W) is required from this pin to GND to control the dc input impedance of the circuit. It has a nominal value of 56 W for low voltage operation. Volume adjustment of ringer and earphone amplifier Output for ringing frequency detection This internal voltage bias line must be connected to VL via an external resistor, RB, which dominates the ac input impedance of the circuit and should be 620 Ω for an 600 W input impedance or 910 Ω for a 900 Ω input impedance. The range of transmit and receive gain variations between short and long loops may be adjusted by connecting a resistor RAGC from this pin to (GND). This pin can be left open to set a.g.c. out of action. DTMF input Control input for DTMF operation Ringer supply Input for setting the DC characteristic 3 (6) Preliminary Information U4037B Electrical Characteristics speech circuit Reference point Pin GND, f = 1000 Hz, 0 dBm = 775 mVrms, RDC = 60 kΩ, Tamb = 25°C, unless otherwise specified Parameters Line voltage Transmit and sidetone Input resistance Gain Line loss compensation Distortion at line Maximum output voltage Anti-clipping attack time Release time Noise at line weighted psophometrically Sidetone reduction DTMF-amplifier Test Conditions / Pin IL = 8 mA IL = 20 mA IL = 30 mA IL = 73 mA Ri IL = 30 mA RAGC = 0 W, IL = 73 mA IL > 15 mA, VL = 775 mVrms IL > 19 mA, d < 5 %, Vmic = 10 mV, RDC = 100 kW Vmic = 20 mV, C = 470 nF Each 3 dB overdrive IL > 30 mA, GS = 48 dB y 20 mA IL y Volume range d 5% Receiving amplifier Gain Amplification of DTMF signal from DTMF IN to RECO1/2 Frequency response Gain change with current Gain deviation Ear protection differential Line loss compensation Receiving noise at earphone psophometrially weighted Gain change when muted IL IF w 20 mA w 15 mA, mute active IL> 15 mA, CL = 4.7 nF, f =300 to 3400 Hz IL = 15 to 100 mA Tamb = –10 to +60°C, IL = 15 mA IL 15 mA, Vgen = 11 Vrms IL = 73 mA IL = 73 mA w IL Output voltage push pull IL Supply voltage Output voltage IL y 20 mA y 20 mA y 20 mA Symbol VL Min 1.8 3.0 3.6 7.7 Typ 2.1 3.3 Max 2.6 3.6 4.5 9.7 Unit V V V V Ri Gs DGs ds V1max 30 47 –5 50 48 –6 1.8 3 75 49 –7 2 4.2 kΩ dB dB % dBm – 72 ms ms dBmp 20 dB 0.5 9 no GSTA 10 V0 1 GR GRM –15 IL w 20 mA VRMS 4 –12 DGR DGR DGR ni –6 – 80 GRM 40 V0 –9 "0.5 "0.5 "0.5 DGRF –5 0.8 0.9 2.2 –7 – 71 dB dB dB dB dB Vrms dB dBm dB 1 Vrms VDDS 3 speech mode Mute suppression 15 GSM 4 (6) Preliminary Information 60 V V dB TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96 U4037B Electrical Characteristics of Tone Ringer Interface Parameters Supply current, outputs open Switch-on threshold Switch-off threshold Volume adjustment range Test Conditions / Pin VRING = 14 V Supply voltage for MCU IDD < 1 mA Symbol IS Min 1.5 VOI1 VOI2 Typ 2.0 Max 2.5 Unit mA 11 6.5 40 V V dB(A) 3.2 V Ordering Information Type U4037B Package SO24 Package Information Package SO24 Dimensions in mm 15.5 15.3 2.7 2.45 9.25 8.75 2.45 2.25 0.3 0.2 0.1 min 0.49 0.35 7.5 7.3 1.27 10.55 10.15 13.97 technical drawings according to DIN specifications 95 11492 TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96 5 (6) Preliminary Information U4037B Ozone Depleting Substances Policy Statement It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances ( ODSs). The Montreal Protocol ( 1987) and its London Amendments ( 1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban on these substances. TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2 . Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency ( EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C ( transitional substances ) respectively. TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. We reserve the right to make changes to improve technical design and may do so without further notice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423 6 (6) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 08-Oct-96